The present invention relates to an apparatus and method for electrical system enclosures. More specifically, the invention relates to an apparatus and method for safely accessing electrical systems.
According to government statistics, one worker gets electrocuted in the workplace each day, and at least five more are admitted to the hospital with electrocution-type burns. As a result, it has become exceedingly important that manufacturers of potentially dangerous electrical equipment, such as bus bar assemblies, design their equipment in such a way that minimizes accidental electric shock to industrial workers.
Many prior approaches protecting against electrical contact have been utilized. Very early approaches include leaving bus bars open and posting signs and tags warning workers of electric shock. These methods have proved highly insufficient and do not protect against accidental contact.
Later, a device known as a manual shutter was provided. The shutter typically included a shutter panel having holes matching those of the mounting panel when the shutter was placed in an open position, so that an electrical device may be installed through the shutter and panel into contact with the bus bars. The shutters typically included one or more web areas between the holes, which cover the electrical connector openings in the panel when the shutter is in the closed position. However, bus bars were exposed before the shutter is manually closed, and during any time period when the shutter has been manually opened.
More recently, there have been different approaches utilizing an automatic shutter mechanism that closes on its own as an electrical device in contact with the bus bars is removed from the enclosure, without any action being taken by a technician or operator. These approaches have included, for example, a shutter operating under the force of gravity via an inclined plane, and shutters using a shutter actuation system, which often include complex arrangements of cams, levers, chains and sprockets. These prior automatic shutter actuation systems have tended to be bulky and complex. Furthermore, these designs must be installed as the assembly is being put together.
Accordingly, to date, there is additional need for a more simple apparatus or method for enclosing electrical equipment.